WASHINGTON (Reuters) - House Speaker John Boehner
warned President Barack Obama Tuesday that he was skating on
thin legal ice by keeping U.S. forces involved in Libya for
nearly three months without the authorization of Congress.

The letter from the Republican leader of the House of
Representatives to the Democratic president threatened to turn
lawmakers' unease over the Libyan conflict into a clash between
Congress and the White House over constitutional powers.

Boehner accused Obama of "a refusal to acknowledge and
respect the role of Congress" in military operations and a
"lack of clarity" about why the U.S. was still involved in
Libya.

He asked Obama to explain the legal grounds for the war by
Friday, adding that by Sunday Obama would be in violation of
the 1973 War Powers Resolution if nothing changed.

The U.S. Constitution says that Congress declares war,
while the president is commander-in-chief of the armed forces.
The War Powers Resolution sought to resolve the tensions in
these roles and was passed by Congress over a veto by President
Richard Nixon.

No sitting president has ever recognized the resolution,
which prohibits U.S. armed forces from being involved in
military actions for more than 60 days without congressional
authorization, and includes a further 30-day withdrawal period.
Boehner said the 90 days expires on Sunday.

"It would appear that in five days, the administration will
be in violation of the War Powers Resolution unless it asks for
and receives authorization from Congress or withdraws all U.S.
troops and resources from the mission," Boehner said in the
letter, which was released by his office.

"Have you ... conducted the legal analysis to justify your
position?" he asked. "Given the gravity of the constitutional
and statutory questions involved, I request your answer by
Friday, June 17, 2011."

CONSULTATIONS

Obama notified Congress in March that the United States was
taking part in a multinational operation conducting air strikes
to protect Libyan civilians from by Muammar Gaddafi's forces.
Obama did not ask for congressional authorization.

There are no U.S. troops on the ground in Libya, where NATO
is leading the intervention with the United States providing
logistical support and intelligence.

The White House says it has consulted regularly with
lawmakers on the war and officials have suggested that the
limited U.S. action might not meet the War Powers threshold.

White House spokesman Tommy Vietor said administration
officials have testified at more than 10 hearings on Capitol
Hill, which included substantial discussion of Libya. Officials
also took part in more than 30 briefings with lawmakers and
staff and would keep engaging with Congress, he said.

"We are in the final stages of preparing extensive
information for the House and Senate that will address a whole
host of issues about our ongoing efforts in Libya, including
those raised in the House resolution as well as our legal
analysis with regard to the War Powers Resolution," Vietorsaid.

If Obama did ask for congressional authorization, it is not
clear he would get it. The Democratic-controlled Senate has not
tried to pass a non-binding resolution supporting the war.

Two House lawmakers, Democrat Dennis Kucinich and
Republican Walter Jones, said they would file a lawsuit in
federal court concerning Obama and the Libyan war.

Earlier this month, a House majority passed a resolution
accusing Obama of not having offered a "compelling rationale"
for the Libyan war and demanding information about its costs
and scope by Thursday June 16. Boehner's letter indicated that
lawmakers are still waiting for answers.

That resolution noted that Congress has the authority to
cut off funds for military operations, implying this might be
considered if the Obama administration did not respond.
(Additional reporting by Laura MacInnis; Editing by Cynthia
Osterman and Christopher Wilson)